1... Bb4+! Ok, it is a bit of a trick question, as the best move is not really the tactic Overload, but rather a Mobility move to set up the tactic. The real Overload comes from 2...Bc3 where the Bishop hits 2 targets: the Rook on a1 and the Knight on d4. Should White play Bd2 to prevent 2...Bc3 then a different Overload is created on the Knight on d4 by removing the Queen support.
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